And the Lord God commanded Moses now teaches, that man was the governor of the world, with this exception, that he should, nevertheless, be subject to God. A law is imposed upon him in token of his subjection; for it would have made no difference to God, if he had eaten indiscriminately of any fruit he pleased. Therefore the prohibition of one tree was a test of obedience. And in this mode, God designed that the whole human race should be accustomed from the beginning to reverence his Deity; as, doubtless, it was necessary that man, adorned and enriched with so many excellent gifts, should be held under restraint, lest he should break forth into licentiousness. There was, indeed, another special reason, to which we have before alluded, lest Adam should desire to be wise above measure; but this is to be kept in mind as God's general design, that he would have men subject to his authority. Therefore, abstinence from the fruit of one tree was a kind of first lesson in obedience, that man might know he had a Director and Lord of his life, on whose will he ought to depend, and in whose commands he ought to acquiesce. And this, truly, is the only rule of living well and rationally, that men should exercise themselves in obeying God. It seems, however, to some as if this did not accord with the judgment of Paul, when he teaches, that the law was not made for the righteous, (1-Timothy 1:9.) For if it be so, then, when Adam was yet innocent and upright, he had no need of a law. But the solution is ready. For Paul is not there writing controversially; but from the common practice of life, he declares, that they who freely run, do not require to be compelled by the necessity of law; as it is said, in the common proverb, that Good laws spring from bad manners.' In the meantime, he does not deny that God, from the beginning, imposed a law upon man, for the purpose of maintaining the right due to himself. Should any one bring, as an objection, another statement of Paul, where he asserts that the "law is the minister of death," (2-Corinthians 3:7,) I answer, it is so accidentally, and from the corruption of our nature. But at the time of which we speak, a precept was given to man, whence he might know that God ruled over him. These minute things, however I lightly pass over. What I have before said, since it is of far greater moment, is to be frequently recalled to memory, namely, that our life will then be rightly ordered, if we obey God, and if his will be the regulator of all our affections. Of every tree To the end that Adam might the more willingly comply, God commends his own liberality. Behold,' he says, I deliver into thy hand whatever fruits the earth may produce, whatever fruits every kind of tree may yield: from this immense profusion and variety I except only one tree.' Then, by denouncing punishment, he strikes terror, for the purpose of confirming the authority of the law. So much the greater, then, is the wickedness of man, whom neither that kind commemoration of the gifts of God, nor the dread of punishment, was able to retain in his duty. But it is asked, what kind of death God means in this place? It appears to me, that the definition of this death is to be sought from its opposite; we must, I say, remember from what kind of life man fell. He was, in every respect, happy; his life, therefore, had alike respect to his body and his soul, since in his soul a right judgment and a proper government of the affections prevailed, there also life reigned; in his body there was no defect, wherefore he was wholly free from death. His earthly life truly would have been temporal; yet he would have passed into heaven without death, and without injury. Death, therefore, is now a terror to us; first, because there is a kind of annihilation, as it respects the body; then, because the soul feels the curse of God. We must also see what is the cause of death, namely alienation from God. Thence it follows, that under the name of death is comprehended all those miseries in which Adam involved himself by his defection; for as soon as he revolted from God, the fountain of life, he was cast down from his former state, in order that he might perceive the life of man without God to be wretched and lost, and therefore differing nothing from death. Hence the condition of man after his sin is not improperly called both the privation of life, and death. The miseries and evils both of soul and body, with which man is beset so long as he is on earth, are a kind of entrance into death, till death itself entirely absorbs him; for the Scripture everywhere calls those dead who, being oppressed by the tyranny of sin and Satan, breath nothing but their own destruction. Wherefore the question is superfluous, how it was that God threatened death to Adam on the day in which he should touch the fruit, when he long deferred the punishment? For then was Adam consigned to death, and death began its reign in him, until supervening grace should bring a remedy.

And the LORD God (l) commanded the man, saying, Of every tree of the garden thou mayest freely eat:
(l) So that man might know there was a sovereign Lord, to whom he owed obedience.

And the Lord God commanded the man,.... Over whom he had power and authority; and he had a right to command him what he pleased, being his Creator, benefactor, and preserver; and this is to be understood not of man only, but of the woman also, whose creation, though related afterwards, yet was before this grant to eat of all the trees of the garden but one, and the prohibition of the fruit of that; for that she was in being, and present at this time, seems manifest from Genesis 3:2.
saying, of every tree of the garden thou mayest freely eat: a very generous, large, and liberal allowance this: or "in eating thou mayest eat" (y); which was giving full power, and leaving them without any doubt and uncertainty about their food; which they might freely take, and freely eat of, wherever they found it, or were inclined to, even of any, and every tree in the garden, excepting one, next forbidden.
(y) "comedendo comedas", Pagninus, Montanus, Vatablus, Drusius, &c.

Let us never set up our own will against the holy will of God. There was not only liberty allowed to man, in taking the fruits of paradise, but everlasting life made sure to him upon his obedience. There was a trial appointed of his obedience. By transgression he would forfeit his Maker's favour, and deserve his displeasure, with all its awful effects; so that he would become liable to pain, disease, and death. Worse than that, he would lose the holy image of God, and all the comfort of his favour; and feel the torment of sinful passions, and the terror of his Maker's vengeance, which must endure for ever with his never dying soul. The forbidding to eat of the fruit of a particular tree was wisely suited to the state of our first parents. In their state of innocence, and separated from any others, what opportunity or what temptation had they to break any of the ten commandments? The event proves that the whole human race were concerned in the trial and fall of our first parents. To argue against these things is to strive against stubborn facts, as well as Divine revelation; for man is sinful, and shows by his first actions, and his conduct ever afterwards, that he is ready to do evil. He is under the Divine displeasure, exposed to sufferings and death. The Scriptures always speak of man as of this sinful character, and in this miserable state; and these things are true of men in all ages, and of all nations.

Thou shall die - That is, thou shalt lose all the happiness thou hast either in possession or prospect; and thou shalt become liable to death, and all the miseries that preface and attend it. This was threatened as the immediate consequence of sin. In the day thou eatest, thou shalt die - Not only thou shalt become mortal, but spiritual death and the forerunners of temporal death shall immediately seize thee.